With the modern day need for high speed mail handling systems, it has been found useful to transport envelopes along a mail handling feed path with a vertical orientation. This vertical orientation requires that many basic functions provided by prior machines, such as moistening and sealing of the envelopes, require new mechanisms due to the differences in the mail handling orientation.
As a prelude to the moistening of envelope flaps, it is required that the flap be separated from the body portion of the envelope. With the vertical orientation of the moving piece of mail, it has been discovered that the flap of an envelope can be distended from the body of the letter by applying a force across the back of the envelope. This force makes the body of the letter flex (breaks-the-back of the envelope). The flexure of the envelope body, in turn, causes the flap of the envelope to distend or otherwise separate from the body of the letter.
The flap separating method and system of this invention further provides a solution to a problem inherent with fixed knife-blade type separators. Fixed blade separators cannot distinguish between sealed and unsealed pieces of mail. As a result, if sealed envelopes are fed into a mail handling system having a fixed blade separator, the nose of the sealed flap will be torn or damaged when coming in contact with the blade. In other words, there is no provision in present systems for by-passing the separator blade should mixed mail (sealed and unsealed) be introduced therein.
The present invention resolves the aforementioned problem, and provides a mechanism and method which can be used with mixed mail (sealed and unsealed).